From 7c11cc1addc0a00e60884f4b3495815d9414c06a Mon Sep 17 00:00:00 2001
From: Rodolfo Granata <rudolph@fb.com>
Date: Thu, 4 Feb 2016 01:28:54 -0800
Subject: [PATCH] Add interface to trigger log-writers to flush their buffers.

Summary: Add interface to trigger log-writers to flush their buffers.

Reviewed By: markw65

Differential Revision: D2895713

fb-gh-sync-id: eeba9121a954665c522717efd23fb6e3fedc9dbe
---
 hphp/runtime/base/crash-reporter.cpp | 6 +++++-
 hphp/runtime/server/access-log.cpp   | 6 ++++++
 hphp/runtime/server/access-log.h     | 3 ++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/hphp/runtime/base/crash-reporter.cpp b/hphp/runtime/base/crash-reporter.cpp
index 8ce3fd84220..6817bc4d064 100644
--- a/hphp/runtime/base/crash-reporter.cpp
+++ b/hphp/runtime/base/crash-reporter.cpp
@@ -22,6 +22,7 @@
 #include "hphp/runtime/base/execution-context.h"
 #include "hphp/runtime/ext/std/ext_std_errorfunc.h"
 #include "hphp/runtime/debugger/debugger.h"
+#include "hphp/runtime/server/http-request-handler.h"
 #include "hphp/runtime/vm/ringbuffer-print.h"
 #include "hphp/runtime/vm/jit/mc-generator.h"
 #include "hphp/runtime/vm/jit/translator.h"
@@ -45,7 +46,7 @@ static void bt_handler(int sig) {
     }
   }
 
-  // In case we crash again in the signal hander or something
+  // In case we crash again in the signal handler or something
   signal(sig, SIG_DFL);
   IsCrashing = true;
 
@@ -121,6 +122,9 @@ static void bt_handler(int sig) {
   Logger::Error("Core dumped: %s", strsignal(sig));
   Logger::Error("Stack trace in %s", RuntimeOption::StackTraceFilename.c_str());
 
+  // Flush whatever access logs are still pending
+  HttpRequestHandler::GetAccessLog().flushAllWriters();
+
   // Give the debugger a chance to do extra logging if there are any attached
   // debugger clients.
   Eval::Debugger::LogShutdown(Eval::Debugger::ShutdownKind::Abnormal);
diff --git a/hphp/runtime/server/access-log.cpp b/hphp/runtime/server/access-log.cpp
index 6b7a1a14d46..543ab19c773 100644
--- a/hphp/runtime/server/access-log.cpp
+++ b/hphp/runtime/server/access-log.cpp
@@ -154,6 +154,12 @@ void AccessLog::onNewRequest() {
   threadData->startTime = TimeStamp::Current();
 }
 
+void AccessLog::flushAllWriters() {
+  if (!m_initialized) return;
+  m_defaultWriter->flush();
+  for (auto& file : m_files) file->flush();
+}
+
 bool AccessLog::setThreadLog(const char *file) {
   return (m_fGetThreadData()->log = fopen(file, "a")) != nullptr;
 }
diff --git a/hphp/runtime/server/access-log.h b/hphp/runtime/server/access-log.h
index 486c35ab37d..601a1b39f8d 100644
--- a/hphp/runtime/server/access-log.h
+++ b/hphp/runtime/server/access-log.h
@@ -78,8 +78,8 @@ public:
   bool setThreadLog(const char *file);
   void clearThreadLog();
   void onNewRequest();
+  void flushAllWriters();
 private:
-
   bool m_initialized;
   Mutex m_lock;
   GetThreadDataFunc m_fGetThreadData;
@@ -97,6 +97,7 @@ public:
   virtual void init(const std::string& username,
                     AccessLog::GetThreadDataFunc fn) = 0;
   virtual void write(Transport* transport, const VirtualHost* vhost) = 0;
+  virtual void flush() {}
 protected:
   const LogChannel m_channel;
   FILE* m_filelog{nullptr};
-- 
2.11.4.GIT